Running cats? If there's no cats that could be why. The back pressure from cats helps low RPM torque. But it shouldn't be THAT noticeable.

Get it tuned. It's prolly running rich now anyway.

These LS PCMs do not require a "relearn" period like OBD1 did. They're pretty quick to learn what is going on.

 

You don't need to waste money on a tune!!!! Drive your car & let the computer learn & adjust.. Wait til you throw a cam in it & then do a tune.. Your stock pcm handle headers just fine & will adjust the fuel trims.

 

^ They do not adjust anything to modifications, there is no re-learn. But it won't hurt the car by driving it around un-tuned, it'll just foul plugs and hurt your gas mileage. And I picked up 30hp from a tune with my LT swap.

 

You are very incorrect sir!!! Do you know what LTFT's & STFT's are??? I had headers on my car back in 02' when alot of tunning sofware wasn't even out yet & a hotcam in it.. Guess what, my car never fouled plugs & only smelled ritch at idle because of the exhaust overlap.. Even had it dynoed & again A/F was fine, car was never dyno tunned on this set-up & made like 365rwhp & stayed that way until 07' when I decided I wanted a better motor & more power.. Point is, the pcm does learn & adjust, but is limited in stock form. It can however, handle headers & small cams just fine.

 

^ Yes I know what long term and short term fuel trims are. But these cars are not self tuning. It can learn and adjust to an extent. And those 98's are not like the 99+ PCMs. Not sure exactly what the differences are. And my cam is considered a "baby-cam" but just because it runs, doesn't mean that it's ok to leave it like that. Especially after a cam install.


And my before RW was 295 with the LT's, lid and Ported TB. After the tune was 336/346.

 

I agree, they aren't "self tunning", but as long as the maf & o2's sensors are working along with no leaks, then the computer will learn & make adjustments.. I'm talking on headers here, not bigger cams or heads.. If the OP has no intentions of ever installing a cam, then yes, by all means invest in a tune & squeeze a lil bit more out of it.. But if a cam is in his future then his car will be just fine until then.. As for the 98's ecm's, they just have less tunning perimeters vs the 99-02s.

 

yeah im running cats, i got the catted tsp y pipe.

 

From everything I read this is correct. The PCM will do some adjusting but not like a tune for maximum efficiency. Take for example on a stock car maximum efficiency is at a 5 and with exhaust it is at a 10, I made up those numbers but you get the point. The PCM will make some adjustments to maybe a 7 but it is not going to adjust to a 10 to maximize efficiency allowing maximum power and MPG. With that said, the car will run fine with headers on it, but it will never reach maximum potential without a tune.

 

I would suggest a tune, mine ran super rich after headers and I also had that lagging feeling.

 

I put PS LT's on my car also.. It felt like there was a little loss in low end torque but not much. The headers simply moveded your power band to higher rpms. Also as everyone stated above you plan on cam and heads later down the road then a tune now with just headers would be kinda waste of money since they can be a little expensive, But if you have no future plans for the car, get a tune and squeeze every bit of power out of it. Also, its very easy to crack a plug when doing a header swap, check them out and make sure there not cracked or anything

 

Ok.. It's just that there seem to be misconceptions about a "re-learn" cycle with these newer PCMs. It's not like an OBD1 system where I had to go through a drive cycle with it before it will act right.

Juts didn't want to get OP into the wrong frame of thinking.

And mine ran super rich after LT install and I was told by a local tuner at the time that it was a good idea to get a reading on it. (2004)

 

im gonna replace plugs and wires soon. yeah i'll probably do cam and heads down the road but i'm gonna do intake soon. after intake i'll probably get a tune.

 

I have a LS6 intake on mine also and no tune. Im pretty easy with it tho and dont drive it much. This winter its gettin heads and cam so I will just wait and do a tune then.

 

'98 TA's represent lol.

 

^^^haha..

 

It feels like I lost some bottom end and gained a tiny when I just did pacesetters and tsp Y a few weeks ago...I have a stock LS6 and had one 02 exhaust manifold on and one 98 exhaust manifold on before that

 

my a4 car felt laggy after the header/exhaust install. in all actuality it gained 8mph in the 1/4 untuned and only about 2 mph after a tune.

for some reason i think the noise deterred me from how hard it was pulling. i guess going from stock exhaust to headers and 3" true duals dumped at the axle will do that for you.

of course going from a near 120 car to a 101 car was confusing...110 still felt slow haha.

 

I'm dissappointed in the way my car drives...I have a
10kmi LS6 crate engine
1 3/4 pacesetter longtubes
TP 3 inch off road Y
hooker muffler & tips
smooth bellow
MTI lid/K&N
MSD 8,5 wires
crank pulley
160 therm/high flow water pump
all the free mods
trans go shift kit
pcmforlesstune(before headers)

stock 3.23 gears...the car is all top end it feels great punching it..but driving around it feels slowwww...my stock Formula 350 felt much peppier which had about 200 hp less and I could swear so did with the stock LS1 and cats on. Do you guys think a full tune is holding me back?

 

^ Most likely. What intake are you running? -LS6, I'd imagine. My throttle response changed a lot with a ported TB. A mail-order tune is good for basic bolt ons and mostly to get you in the ball-park for anything more. But a true real-time data log based tune is the only way to get it dead-nuts on.

Sorry, but I'm a big fan of tuning the correct way. (I've been burned before.) But then again, my car seemed to have "woken up" at about 35k miles. (2006) so it felt like it naturally started pulling a little harder. I think that's the point when it broke in. Maybe your 10k mi LS6 is still a little tight.

 

with regard to the ls6 engine...did the factory ls6 cars have a different stock tune vs an ls1 engine?

i'd have the ls6 tuned just because i'd hate to spend all that cash on a crate ls6, swap it, and still run like an ls1. get it tuned properly and you should see some nice gains and power everywhere.